Process for the concentration of beryllium and aluminum minerals



United States Patent OH 3,377,159 PROCESS FOR THE CONCENTRATIDN F BERYL- LIUM AND ALUMINUM MINERALS Orrin F. Marvin, 1549 W. Madison, Phoenix, Ariz. 85007 No Drawing. Filed Oct. 1, 1964, Ser. No. 400,930 5 Claims. ((11. 75101) ABSTRACT OF THE DISCLOSURE My invention relates to a method of treating aluminum and beryllium oxides to change them from a relatively hydrophilic mineral to a highly hydrophobic particle so that these oxides can be easily removed by flotation from impurities found in these ores.

My invention relates in general to the concentration and recovery of beryllium from its ores. It relates more in particular to a method of treating beryllium contained minerals such as beryl, chrysoberyl, bertrandite, phenacite, euclase and other such beryllium contained minerals.

Many deposits of beryllium mineralization are known in the United States that cannot be economically worked by presently known methods.

The principal object of my present invention is the provision of/ and means for treating such beryllium minerals to change the magnitude of the contact angle of the beryllium minerals so that flotation is readily achieved.

Another object is the provision of/ and means for treating aluminum oxide ores to change the contact angle of the aluminum oxide particles so that concentration by flotation can be readily achieved.

In accordance with the general features of my present invention I first prepare the ore to be treated by crushing and/or grinding to a size best suited to the particular ore. I then heat the prepared ore in the presence of a hydrocarbon gas at a temperature above 1000 F., preferably 1300 to 1500 F., for a variable length of time depending on the particular ore.

Under these conditions of atmosphere and temperature the beryllium and/or aluminum mineral absorbs carbon and possibly some hydrocarbon, which changes the contact angle of the beryllium or aluminum particle. It also may be said this changes the mineral particle from a hydrophilic to a highly hydrophobic particle. The pronounced affinity of these two minerals to absorb carbon or hydrocarbon under the above-mentioned conditions supplies a very eflicient means for separation of these two abovementioned elements from other constituents which may be in the ore.

I have found that there is a marked difference in the degree of afiinity between aluminum oxide and beryllium minerals to absorb carbon; aluminum oxide has a much higher aflinity than beryllium minerals. This character difference can be used for the separation of beryllium minerals from aluminum oxide by control of time and contact with a heated hydrocarbon gas.

As an illustration, I treated a 100 mesh pigmatite ore assaying 0.24% beryllium oxide contained in the minerals, bertrandite and penacite, by heating at 1450 F. in the presence of natural gas for 30 minutes and then cooled out of contact with air. I then treated the cooled ore by flotation, using an unusually small amount of frother and adjusted the pH to 12. No collector was used. It was necessary to employ a wetting agent to force some of the material below the slurry surface before the introduction of air. (Some of the treated ore would not wet without the use of a wetting agent.) The floated product obtained assayed 16.2% BeO with only a trace of iron.

3,3 77,15 9 Patented Apr. 9, 1968 The tails from this flotation step were substantially free of beryllium and contained nearly all the iron and free silica.

To further illustrate, I treated an ore containing 8.4% A1 0 6.1% Fe O 3.9% C210 and 1.9% TiO the balance being silica and water of crystallization. This ore was ground to 100 mesh and heated at 1400 F. in the presence of natural gas for a period of 15 minutes and cooled out of contact with air. The cooled product was treated by flotation using 2 drops of No. 63 frother in 4000 milliliters of slurry, the pH adjusted to 12 and a wetting agent was added.

The floated product assayed 69.3% A1 0 0.036% Fe as FeO, the balance being aluminum silicate and free silica with only traces of C210 and TiO Acid leaching of these floatation concentrates is sometimes desirable, to further purify by removing small amounts of iron, zinc, copper and other acid soluble constituents.

When I mention acid in this sense, I have in mind in sulphuric and hydrochloric but not hydrofluoric.

Terms in the specifications and in the claims are, in general, used in their usual sense in art unless the context indicates to the contrary.

Finally, though I have explained and illustrated my invention in detail so that those skilled in the art will understand the manner of practicing the same, the scope of the invention is defined in the claims.

I claim: 1

1. A process for treating oxides selected from the group consisting of aluminum and beryllium to change said oxides from relatively hydrophilic oxides to highly hydrophobic oxides which comprises: heating said oxides in a hydrocarbon atmosphere at a temperature above 1000" 'F.

2. A process for treating oxides of aluminum to change said oxides from relatively hydrophilic oxides to highly hydrophobic oxides which comprises: heating said oxides in a hydrocarbon atmosphere at a temperature above 1000 F.

3. A process for treating oxides of beryllium to change said oxides from relatively hydrophilic oxides to highly hydrophobic oxides which comprises: heating said oxides in a hydrocarbon atmosphere at a temperature above 1000 F.

4. A process for treating oxides of aluminum to change said oxides from relatively hydrophilic oxides to highly hydrophobic oxides which comprises: heating said oxides in a hydrocarbon atmosphere at a temperature above 1000" F. and then subjecting the treated ore to froth flotation.

5. A process for treating oxides of beryllium to change said oxides from relatively hydrophilic oxides to highly rydrophobic oxides which comprises: heating said oxides in a hydrocarbon atmosphere at a temperature above 1000 F. and then subjecting the treated ore to froth flotation.

References Cited UNITED STATES PATENTS 738,733 9/1903 Reuterdahl -68 3,211,524 10/1965 Hyde et al 75-l0l FOREIGN PATENTS 72,644 11/1929 Sweden.

OTHER REFERENCES Journal of Mines: Metals and Fuels, Venkatadas, R.,

W. W. STALLARD, N. F. MARKUA,

Assistant Examinenr. 

